'Blueprint' for universal flu vaccine revealed
Scientists have discovered the "blueprint" for a revolutionary universal flu vaccine that could protect against all strains of seasonal influenza – even deadly new viruses never encountered before.
A study that involved a rapidly organised "natural experiment" triggered by the swine-flu pandemic of autumn 2009 has uncovered strong evidence that a set of naturally occurring immune cells could play a crucial role in the body's resistance to flu.
More than 300 staff and students at Imperial College London were recruited for the study at the start of the pandemic and their conditions monitored for the length of the outbreak.
The findings were published in the journal 'Nature Medicine' yesterday. Those who avoided severe illness were found to have more CD8 T cells, a type of virus-killing immune cell, in their blood at the start of the pandemic.
Professor Ajit Lalvani, from the National Heart and Lung Institute at Imperial College London, who led the study, said a vaccine that made the body produce more of these cells had the potential to be "the Holy Grail": a universal vaccine effective against all strains of flu.
"The immune system produces these CD8 T cells in response to usual seasonal flu," Professor Lalvani said. "Unlike antibodies, they target the core of the virus, which doesn't change, even in new pandemic strains."
Existing flu vaccines make the immune system create antibodies that recognise structures on the surface of the virus, to prevent infection with the most prevalent current strains.
However, health authorities are often one step behind as new viruses with different surface structures are constantly evolving.
Health authorities welcomed the study.
Dr Richard Pebody, responsible for flu surveillance in the Respiratory Diseases Department at Public Health England, said: "Influenza is continually evolving and it is difficult to predict what strains will emerge each year.
"These findings contribute to the science to determine if it is possible to develop a universal vaccine to protect a population against all strains."